Container transfer apparatus with automatic positioning compensation

ABSTRACT

An apparatus for transferring a specimen container from a departure support to a container which includes a gripper supporting frame and a container gripper selectively movable with respect to the frame between an upper position and lower position in which gripper fingers of the container gripper are able to catch a container in a departure support or to leave the container in a container carrier. The apparatus further includes a gripper blocking element movable between a work position, in which said gripper blocking element stops the movement of the container gripper towards the lower position in an intermediate position between the upper and lower positions, and a rest position in which the gripper blocking element allows the container gripper to reach the lower position sliding along the lateral surface of the container.

BACKGROUND OF THE INVENTION

The present invention concerns a container transfer apparatus whichallows automatic compensation of possible erroneous positioning of thecontainer in a container carrier.

As used herein, the term “container” means an article that contains abiological specimen and has a tubular opening for access of thecontents, e.g. a test tube.

At the entry in an automated clinical chemistry laboratory it isrequested to transfer a specimen container from a departure support,such as an input/output module (IOM), to a container carrier (forexample as disclosed in PCT application No. PCT/EP2006/067294 of thesame Applicant) which is then moved by a motorized conveyor belt througha succession of workcells.

There are known container transfer apparatus comprising a fixed frameand a container gripper movable between an upper position and a lowerposition.

When in the lower position the container gripper grips a containerplaced in the departure support by means of movable fingers, thenupraises and is moved over a container carrier placed on a conveyorbelt.

Finally the container gripper goes down to position the grippedcontainer inside the container carrier.

The vertical distance of the container gripper between the upperposition and the lower position is standard, while the vertical positionof the container in the departure support, namely the IOM, may vary asfor human mistakes that do not grant the correct contact of the bottomof the container with the abutment plane surface of the departuresupport.

If the container is not correctly positioned in the departure support,the gripper fingers of the container gripper catch the container lowerthan usual.

As a result, when the container gripper places the container into thecontainer carrier, the bottom of the container is not in contact withthe abutment plane surface of the carrier, that is the container is notcorrectly positioned in the carrier.

An incorrect positioning of the container in its carrier may cause a lotof problems during its passage through the several workcells.

SUMMARY OF THE INVENTION

Object of the present invention is to provide a container transferapparatus which allows sure correct positioning of the container in thecontainer carrier.

According to the invention said object is achieved by an apparatus fortransferring a specimen container from a departure support to acontainer carrier, comprising a gripper supporting frame and a containergripper selectively movable with respect to said frame between an upperposition and a lower position in which gripper fingers of the containergripper are able to catch a container in a departure support or to leavethe container in a container carrier, characterized by comprisinggripper blocking means movable between a work position, in which saidblocking means stop the movement of the container gripper towards thelower position in an intermediate position between said upper and lowerpositions, and a rest position in which said gripper blocking meansallow the container gripper to reach the lower position sliding alongthe lateral surface of the container.

With the blocking means in the work position the container gripper istherefore stop in an intermediate position in which the gripper fingerscan catch the container in the departure support whichever is itsvertical position. The container gripper is then moved above adestination carrier and with the blocking means in the rest position itis lowered to the lower position where it leaves the container with thecontainer bottom in contact with the abutment plane surface of thecarrier by making the gripper fingers to slide vertically along thelateral surface of the container. In this way, possible containerpositioning mistakes are prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics and advantages of the present invention will appearevident from the following detailed description of an embodiment thereofillustrated as non-limiting example in the enclosed drawings, in which:

FIG. 1 is a perspective view of an apparatus according to the presentinvention with the blocking means in the work position;

FIG. 2 is a perspective view of an apparatus according to the presentinvention with the blocking means in the rest position;

FIG. 3 is a lateral view of the apparatus with the container gripper inthe intermediate position;

FIG. 4 is a sectional view according to line IV-IV of FIG. 3;

FIG. 5 is a sectional view similar to FIG. 4, but with the blockingmeans in a rest position, thus with the container gripper in the loweredposition;

FIG. 6 is a lateral sectional view showing the positioning of thecontainer onto the destination support.

DETAILED DESCRIPTION OF THE INVENTION

A container transfer apparatus 1 is shown in FIGS. 1-5 for the transferof a container 2 from a departure support of an input/output module to acontainer carrier 20 (destination support, FIG. 6) movable on amotorized conveyor belt.

The transfer apparatus comprises a container gripper 3 selectivelymovable by a carriage 4 along a vertical guide 5 and a vertical guidingbar 7 of a supporting frame 6 between an upper position 101 and a lowerposition 103. The container gripper 3 includes movable catching fingers8.

The apparatus 1 also comprises a blocking cursor 9, which is driven tobe selectively movable between a rest position (FIG. 2) and a workposition (FIG. 1), and shock absorber members 13. The cursor 9 is drivenby a pneumatic device 10 comprising a pneumatic piston 11.

In said work position the cursor 9 engages a rigid member 12 fixed tothe carriage 4, so that the container gripper 3 is stop in anintermediate position 102 between said upper position 101 and said lowerposition 103.

Firstly considering the container gripper 3 in the upper position 101over a specimen container 2 positioned in a departure support, thecontainer gripper 3 goes down to the intermediate position 102 (FIGS. 3and 4) with the cursor 9 in the work position of FIGS. 1, 3 and 4engaged with the rigid member 12.

The vertical distance between the intermediate position 102 and thelowered position 103 (see FIGS. 4-5) is enough to achieve theaforementioned object of the invention.

Thus, the container 2 is caught higher than if the cursor 9 were in therest position.

Then the container 2 is upraised and the frame 6 is driven to put thecontainer 2 over the container carrier 20 (FIG. 6).

The container gripper 3 is now moved to the lower position 103, with thecursor 9 being in the rest position of FIGS. 2 and 5.

If the bottom of the container 2 touches the abutted plane surface 21 ofthe container carrier 20 before the end of the run of the gripper 3, thefingers 8 slide on the external lateral surface of the container 2 whichis already correctly positioned (FIG. 6).

Obviously the pushing force of the gripper 3 is higher than the catchingforce of the fingers 8.

Finally the gripper 3 leaves the container correctly positioned.

With a very simple device, a perfect positioning into the destinationsupport is achieved.

The invention claimed is:
 1. An apparatus for transferring a specimencontainer from a departure support to a container carrier, comprising: agripper supporting frame and a container gripper selectively movablewith respect to said gripper supporting frame between an upper positionand a lower position in which gripper fingers of the container gripperare able to catch a container in a departure support or to leave thecontainer in a container carrier; and gripper blocking means movablebetween a work position, in which said gripper blocking means stopsmovement of the container gripper towards the lower position, in anintermediate position between said upper and lower positions, and a restposition in which said gripper blocking means allows the containergripper to reach the lower position sliding along a lateral surface ofthe specimen container if the bottom of said container touches anabutted surface of the container carrier before said container gripperreaches the lower position.
 2. The apparatus according to claim 1,wherein said gripper blocking means comprise a blocking cursor which ismovable in a transversal direction with respect to the direction ofmovement of the container gripper between the upper and lower positions.3. The apparatus according to claim 2, wherein said container gripper isfixed to a carriage movable along a vertical guiding means of saidgripper supporting frame.
 4. The apparatus according to claim 2, whereinsaid gripper supporting frame comprises shock absorbing means for saidcontainer gripper.
 5. The apparatus according to claim 1, wherein saidcontainer gripper is fixed to a carriage movable along a verticalguiding means of said gripper supporting frame.
 6. The apparatusaccording to claim 5, wherein said carriage includes a cursor engageablepart.
 7. The apparatus according to claim 6, wherein said grippersupporting frame comprises shock absorbing means for said containergripper.
 8. The apparatus according to claim 5, wherein said grippersupporting frame comprises shock absorbing means for said containergripper.
 9. The apparatus according to claim 1, wherein said grippersupporting frame comprises shock absorbing means for said containergripper.